Turn indicator



' Jan. `19, 1932. P KQLLSMAN 1,841,607

Y TUN INDICATOR Filed July 3, 1929 ngi Patented' Jan. 19, 1932 ori-"ica EN DH'DICATOR .fipplimiml me@ my e, 192e. serial Nu. 375,612.

rThis invention relates to turn indicators, and has among its objects the provision of an improved device of the nature set forth in which the momentum of a uid moving along a predetermined path is utilized for showing a directional change.

Another object of the invention is to provide a device of the character described having means to guide a iuid stream for movement in any given relation to the movement of the device, while permitting-the Vstream to move in a diiferent relation when the device makes a turn, and indicating means responsive to a change in the movement of the stream.v

A further object of the invention is to furnish a simplified turn indicator. y

A further object of the invention is the provision of improved means that are sensitive to their relation with the fluid stream.

Other objects and advantages of the invention will become apparent as the specification proceeds. v

With the aforesaid objects in view, the invention consists in the novel combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subjoined claims, and illustrated 0n the annexed drawings, wherein like parts are designated by the same reference characters throughout the several views.

The term indicator as used herein lis'intended to include anv device that responds to any change in the iiuid stream, and which may even control or operate any other device, as maybe desired, when alturn occurs. 'In thedrawings: v Figure 1 is a sectional view of a device embodying the invention. .i

Fig. 2 is a sectional view thereof taken on line :f-2 of Fig. 1. l

Fig. 3 is a modification of the invention 'A showing a Pitot tube arrangement. 45 Fig. 4 is a sectional view taken on lined- 4 of Fig. 3. y

Fig. 5 is av form of the invention lwitha modified Pitot tube arrangement.

Fig. 6 is a modiiication of the invention having a Venturi tube.

.confined to one side of the Fig. 7 is another modification of the invention having entrance and outlet cones.

Fig. 8 is a View preferably in vertical section of the invention with a movable member along the fluid stream to operate an indicator.

Fig. 9 is a top plan view of the same.

Fig. 10 is a modification of the invention in which the movable member encloses a portion of the stream.

Fig. 11 is a top plan view thereof.

Y VFig..12 is a further modification in which a deflector or valve element responsive to the fluid stream coacts with spaced indicator points. i

Fig. 13 is a top plan view thereof. Y

Fig. 14 is a further modification in which the deiiector encloses the-fluid stream.

Fig. 15 is a sectional view of a further modification of the invention? in which the indicating means is responsive to temperature or some other condition which is affected by the iiuid stream.

' Fig. 16 is a still further modification in whichthe source of a iiuid stream is shown, and a secondary change, in the flow of current, produced by temperature variation due to the stream. A

Fig. 17 is a view in section of a modification of the invention with the region of response plane of the device.

The advantages of the invention as here outlined are best realized when all of its features and instrumentalities are combined in one and the samestructure, but, useful devices may be produced embodying les's than the whole. Y

It will be obvious to those skilled in the art to which this invention appertains, that the samemay be-incorporated in several different constructions. The accompanying drawings, therefore, is submitted as showing merely the preferred exempliication ofthe invention.

Generally described, the invention pro-V vides a turn'indicator in which the momentum of a fluid stream is used to vshow a `change in direction. The Huid used may be A a gas or a liquid, and, among the former air may be mentioned. By using a fluid in vmotion, the kinetic energy thereof is available to produce a greater reading on an indicator. The device gives a predetermined d1# rection to the fluid stream, and is intended to render vthe flow comparatively smooth anduniform. When a turn occurs, the fluid stream moves in a second path or direction relative to the device and affects any suitable means that is responsive thereto, or to the change mentioned. It is not desired to limit the invention as to ythe indicating means,

. and only a few of the many possible arrangements are shownherein, the same being illustrative merely. The indicating means may be influenced by the fluid stream in a direct mechanical manner, with or without the coaction of an auxiliary stream guide or deflector, or by affecting a condition ofthe indicator to render the same directly yresponsive, or to produce a secondary change which causes the indicator to .show a turn. The` speed of the turn is shown by the amount of the deflection on reading. If the fluid used is to be conserved, it may be recirculated in an obvious manner, and the flow may be caused either by suction or pressure, depending on which produces the smoothest flow.

The direction of the fluid stream directing means may bedefined as being at any angle,

the turn, such change may be electrical, ther mal, or even chemical, and for the electrical changes may be mentioned those produced by a variation in temperature of a resistance (indirect) or a thermocouple (direct).

Referring in detail to the drawing, 20 denotes a device embodying the invention. The same includes a straight channel or tube 21 that is smooth interiorly, 4and is of a suitable length to give direction s to the fluid stream 22. Preferably a suitable inlet connection from an end 23 of the tube is shown at 245 in Fig. 16 and includesl a straight run of plpe to permit the 'low to become as uniform as possible. The velocity of the fluid stream through the tube 21 may be regulated according to the sensitivity of the indicating means, and it may also depend in part upon the density of the fluid used. The velocity of the fluid stream will in turn be a factor in determining the length of the tube 21, as the tube ought to lincrease somewhat in length with an increase in velocity. The liuid may be discharged from the tube at the end 25 thereof, and if it is to be recirculated, a. suitable connection ma?l be made at this end.

In spaced re ation to the end 23-of the tube, l

nections 26, 27 are in any desired relation,

preferably disposed on opposite sides of a vertical plane that extends fore and aft of the aircraft or other vehicle on which the deviceis used. The parts-at the said connections mav lie in the surface of the tube pressure primarily.

The operatlon of the device may' be best understood by tracing throughv the tube a portion of a fluid stream. Entrance into the v by arrows b. Consequently the pressure on port 27 will be greater thanat 26, and the indicator will show accordingly. The velocity head will also make itself effective to some to receive 'IIS' vwall on the right side 4of the tube as shown p extent due-to the angle of the fluid stream with respect to the port 27. If the indicator used is of a type that is responsive to diii'erential pressure, the reading may be increased by the suction zone at 26, which will result from the change in path ofthe stream, If the turn is counter clockwise, the same opera.- tion will occur, but in opposite direction.

Within the scope of the invention the connections 2.6, 27 may also be made'at 90 or any other angle 'with respect to each other, and need not be 180 apart, and in fact the connections can be spaced apart on the same side of the plane referred to, since the diiferential pressure between the points due to a change in path of the fluidstream, will operate the indicator. This applies also to other forms of the invention. A

In Figs. 3 and 4 is shown a modification of the invention including a tube or direction channel 21a having an enlarged entrance 23a which may be in the nature of an orifice that is properly proportioned to ericiently conduct the fluid from a supply pipe of large diameter into the device. In a large pipe, the velocity is low, thus causing a very uniform flow to obtain. This feature of the invention' is, of course, applicable in anyofthe forms of the invention shown. Coacting with the member 21a are a plurality of Vlitot tubes 29, 30. extending through the wall of the tube and spaced along a diameter in proximity to the outlet end 25a of the device. An indicator 28a is connected to the Pitot tubes in any suitthe axis of the device, the fluid stream acts primarily on one of the Pitot tubes, and the indicator needle responds in direction to the superior force.

In Fig. 5 is shown a modification of the invention wherein a. tubular stream guide 21?) has co-operating therewith a plurality of spaced Pitot tubes 29a, and 30a, that connect with an indicator 286. The Pitot tubes are at the outlet end of the stream guide, and

outlet cone assures a smooth and even stream line iiow past the connections.

In Fig. 7 is shown a form of the invention in which a Venturi tube 21d acts as the directionguide for the fluid stream, this tube including the conventional inlet and outlet cones 32, 33. At the throat 34 are connections 290 and 30o disposed on opposite sides of a vertical plane that runs fore and aft of the airplane or the like on whichthe device is used. An indicator 280 of any suitable type communicates with the connections. According to this modification, a high velocity is readily obtained together with a stream line flow. The arrowsfor the 'fluidl stream show that a right turn is-being made.

In Figs. 8 and 9 is shown another modification of the invention including a guide passage 21d through which the iiuid is adapted to flow, and which, like the other forms of the invention is stationary in relation to the aircraft on which the device is mounted. Pivotally mounted at 35 in the guide passage is a movable member or vane .36 of extended area, disposed in or parallel to the vertical longitudinal plane of the aircraft: When a turn is made, and the iiuid assumes a path at an angle to the said plane, it acts over the entire area of the vane 36. rlhus a considerable force is available for actuating. an indicator 28d. In the latter, the pointer 37 is pivotally supported at 38 and connected with the free end of the movablevane 36 by a link 39: The vane maybe Hat as shown, or of any other desired shape to conform to the fluid stream, and to obtain the greatestsensitivity of the device.

In Figs. 10 and l1 isshown another modiiication of the invention in which a direction tube 210 is used, and-the iiuid stream therefrom actuates a movable member 36a that is spaced longitudinally with respect to the said tube. This arrangement .is thus'distingushed from the preceding modification in which the .mounted at 350 a tube 36e.

cylinder shown, which is pivotally mounted v at 35a.` The element 36a is normally in alinement with the tube or nozzle 21o, and is of somewhat larger diameter to receive the fluid streamin any angular position of the former.

The pivotal axis at 35a lies, of course, in the,

vertical longitudinal plane of the aircraft. Theindicator 28e is connected with the element 36a b any suitable means such as the link 39a. FVhen a turn occurs, the fluid stream acts angularly on an area that is equal to that at the diameter of the movable element, and the resulting force readily operates the device. f

. The preferred embodiment of the invention is that shown in Figs. l() and ll. In

Athis embodiment the tube 21e acts as a" direction determining and iiow equalizing means, reducing to a minimum variations of direction, feed and iow of the air. Since the iow passage 36a is itself responsive to a change in direction ofthe air stream, a relatively large delection may be obtained, as the How passage may move through any desired angle, and yet the cross sectional area of said be desired.

In Figs. V12 and 13 is shown a further modiiication of the invention in which a relatively stationary guide tube 2.1]c has an axis 35h in proximity to the upper end thereof, on which is pivotally mounted a vane 365. On the lower end 'thereof is a deiiector or valve 40 which in the usual position, lies between the Pitot tubes 29d and 30d. When a turn occurs, the said deiiector is moved by the vane 365 to cover one of the said tubes, so that the other alone will be acted on by the uidstream. The deflector 40 is intended to be so shaped as to conform as far as possible to the stream line flow, whereby the accuracy of the reading will be assured.

In Figi/lis shown a still further modification of the invention including a' nozzle 21g,

or the like, at the outlet whereof is pivotally At the outlet of the latter are a pluralityof Pitot tubes 29o and 30o which-are spaced on opposite sides of a vertical plane passing through the pivot 350, and with reference to which plane the turning. occurs. The said Pitot tubes have `relatively large entrances 41, and connect with a suitable indicator 28g. When a turn occurs,

the fluid stream deflects the tube 360 and is Vdischarged against lbut oneof the Pitot tubes,

the indicator registering accordingly.'

In Fig.' 15 is shown a further modification of the invention in which a direction tube or nozzle 21h discharges a fluid into a chamber 42.A This may be variously shaped depending onthe flow conditions, and can also bein flow passage may be made as small as may 95 the nature of a cone as shownat 33 in Fig. 7. Spaced from the inletl of the cone are a plurality of thermocouples 43, 44 which are on opposite sides of the reference plane of turn- L 5 ing.

The fluid stream is at a temperature other than that at the thermocouples. The latter operate a galvanometer`44a and when the fluid stream due to a turnacts on one of the thermocouples,.the latter no longer balance, and the indicator registers a turn. Any suitable means may be used for causing the temperature variations specified.

In Fig. 16 is shown a further modification o f the invention in which a flow directing element Qlidischarges a fluid into ak chamber 42a, at an outlet whereof are a plurality of spaced electrical resistances 45, 46. are connected into a circuit 47 in .which the currents are counteracting. Connected into 20 the circuit is any suitable galvanometer 48. The element 2li supplies a fluid at a temperature other than thatat the resistances to change the degree of resistance by producing a variation in temperature. Thus the resistrected may have the temperature thereof either increased or decrease able source as, for example, -a centrifugal blower 49 which discharges the fluid through a heater 49a and thence' through a straight run of pipe 24of suitable length to equalize the flow. The said pipe may have an annularof the device on the density of the fluid meL the fluid deflected as shown by the arrows, a

diuml can be counteracted by a suitable control, or by calibration of the indicator dial.

It lwill thus be seen that I have provided a device which fulfills the several objects of the invention and which is well adapted to meet the conditions `of practical use.

In Fig. 17 is shown a further modification of the inventionincluding a flow passage in the form of a Venturi tube 33a with which coacts any suitable indicator 28h. 'In this device it is clearly illustrated that the connections 297 and 307 maybe on one side of the central plane ofthe device. With the path of differential pressure exists betweenthe points 297 and 307e which vmay actuate indieating means of various types. This differential pressure exists since at the point 29f thereexists a reduced pressure while at 30) the pressure is greater, according to the .wellknown theory of venturi. If the turn' is in the opposite direction, the di'erential pressure will different, or it may be less, and

These ance against which the fiuid stream is dias the case may be. The Huid stream is taken from any suit-1 connections 297 and 30 on opposite sides of n the axis, or as shown in ig. 7 The reason is that a much stronger pressure or suction, (as the case may be, depending on different fac, tors or the direction of the turn) is obtained; and the invention must be responsive to a change in direction of a given relatively small mass of air.

I claim: A

1. A turn indicator comprising an element for giving direction to a fluid stream, and indicating means turning with the element and being responsive to a change in the path of the fiuid stream withrespect to said means.

2. A turn indicator for aircraftcomprising Imeans for causing a fluid to flow along a predetermined path, an indicator, and other means affected by a relative change in the path of theI fiuid to cause thel indicator to show a turn. i.'

3. A 'turn indicator for aircraft comprisinga single fluid stream directing means, other means disposed'in predetermined relation with respect to 'said directing means' so as to be affected by the said fluid stream when the aircraft makes a turn, the second mentioned means including an indicating device to show theoccurrenceof the turn.

4. A turn indicator for aircraft lcomprising a member to guide a Huid to flow along a given path, means arranged with respect to any axis about which a turn is to be made to be responsive to la change. in the fluid stream with relation to said axis, caused by a turn of the aircraft, and an indicator operated by said means on response of the latter as aforesaid.V

5. A turn indicator for aircraft, or thelike, comprising a channel to cause a fluid to flow in a predetermined path, means disposed substantially symmetrically with respect to said path on, opposite sides thereof and acted upon by said fluid, and other means coacting with. the second mentioned means to indicate-a turn. f v

6. A turn indicator for aircraft, or the like, comprising means'vto cause a flow of' fluid, other means to cause the fluid to fiow in a given path, said Huid changing its path due to its momentum with respect to the secondf mentioned means, on the voccurrence of a turn of the aircraft, and means responsive to the momentum of the fluid to be affected bya change in the path thereof. l

7. A turn indicator for aircraft, or the like, comprising means to cause a flow of fluid, other means stationary with respect to the iaircraft to 'cause the fluidto flow in a predetermined path, the vfluid automatically 8. A turn indicator for aircraft, comprising a source of a fluid stream, means to cause the same to ovv in a predetermined path with respect thereto, an indicator, and'spaced tubular connect-ions from the indicator to the fluid lstream on opposite sides of the path thereof to respond to a change of the latter'relative to said first mentioned means on occurrence of aturn.

9. A turn indicator for aircraft, comprising a source 0f a fluid stream, means to cause the same to How in a predetermined straight path, and means extending along the said path and acted on by the fluid stream when the latter changes its vpath relative to the first mentioned means due to the momentum of the -liuid on occurrence ofa turn of the aircraft, and an indicator'actuated by the second mentioned means.

10.` A turn indicator for aircraft, comprising means to cause a Huid stream to flow in a predetermined path, an indicator, thermosensitive means disposed in proximity to said path, said fluid varying the temperature of theI thermosensitive means on a change in direction of the path ofthe fluid relative to the thermosensitive means' due to the momentum A of the former, when a turn is made.

' 11. A turn indicator for aircraft, comprising means to causev a iuid stream to flow uniformly and in a predetermined path, elongated tubularmeans of relatively considerable area extending along the said `path and receiving the fluid stream to be acted on over substantially its entire area by the fluid stream 40 due to the momentumof the latter whenfthe same changes its path relative to the firstmentioned means on occurrence of a turn of the aircraft and an indicator actuated by the second vmentioned means.

12. A turn indicator for aircraft, comprising a source of a fluid'stream, means t0 cause the same-to iow in a predetermined relative path, an indicating means, andspaced elements in prom/ixty tosaid path and coacting 5 with the indicating mean's, each of said-elements being substantially sensitive to the energy of the Huid-stream if the ath of the latter changes with respect to saidp means due to the momentum of the fluid st ream, to indi- 55 cate the direction `o f turning.

13. A turn indicator comprising a source of a fluid stream, means to render the iow of the stream substantially uniform, and to cause the stream to flow in a predetermined-straight path relativeto said means, said vuidlstreamK` changing with respect tQsanmeansduriDg a turn, and other means responsive tothe energy ofthe fluid stream to' indicate the 85 changein path'.

14. A turn indicator comprising a source of a Huid stream, means to render the flow of the stream substantially uniform, and to cause the stream to How in a predetermined path relative to said means, saidv means including a conical tube, receiving said fluid stream, said iiuid stream changing its path with respect to said means during a turn, and other means coactin .with said conical tube and responsive to t e energy of the iuid Stream to indicate the change in path.

In testimony whereof-I aliix my signature.

^ PAUL KOLLSMAN. 

